Shiny app unresponsive after R session's tempdir is deleted

I have a shiny app deployed locally via RScript.exe and runApp on a Windows 10 machine which runs just fine. However, when the app is idling for a few days the browser displays the following:

image
This seems to be unrelated to the apps content (otherwise I would have provided an example app).

I was able to generate a log file which gave me:

Warning in file(open = "w+") :
cannot open file 'C:\Users\USER\AppData\Local\Temp\RtmpO0mnd9\Rfdd88a66def': No such file or directory
Warning: Error in file: cannot open the connection
[No stack trace available]

... and indeed the according folder generated on starting up the R session and the files generated on starting the shiny app were deleted (automatic cleaning done by Windows? - I'm not sure why).

I am able to reproduce this error when I'm manually deleting the R sessions tempdir() hosting the shiny app.

Does anyone know how to prevent this issue?

In this GitHub issue Dean Attali suggested using tempdir(check = TRUE) in shiny's source code what seems reasonable to me.

Here is some more related content:
RStudio community topic
SO question

Edit: here is how to reproduce the behaviour:


Edit:

Here is an example application showing the problem:

# Windows shell required
tempdir()
dir.exists(tempdir())

library(shiny)

shinyApp(
    ui = fluidPage("Please reload to see me fail."),
    server = function(input, output) {
        shell(paste("rmdir", dQuote(
            normalizePath(tempdir(), winslash = "/", mustWork = FALSE), q = FALSE
        ), "/s /q"))
    }
)


By now I've found a setting in Windows 10 (Storage Sense) concerning the deletion of temporary files, which seems to be active by default.

Navigate as follows and uncheck:

  1. Settings
  2. System Storage
  3. Storage Sense
  4. Change how we free up space automatically
  5. Delete temporary files that my apps aren't using

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